Tejun Heo f5c16f29bf sysfs: make sure read buffer is zeroed ... 13c589d5b0 ("sysfs: use seq_file when reading regular files") switched sysfs from custom read implementation to seq_file to enable later transition to kernfs. After the change, the buffer passed to ->show() is acquired through seq_get_buf(); unfortunately, this introduces a subtle behavior change. Before the commit, the buffer passed to ->show() was always zero as it was allocated using get_zeroed_page(). Because seq_file doesn't clear buffers on allocation and neither does seq_get_buf(), after the commit, depending on the behavior of ->show(), we may end up exposing uninitialized data to userland thus possibly altering userland visible behavior and leaking information. Fix it by explicitly clearing the buffer. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Ron <ron@debian.org> Fixes: 13c589d5b0 ("sysfs: use seq_file when reading regular files") Cc: stable <stable@vger.kernel.org> # 3.13+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2014-05-20 10:15:53 +09:00
..
Kconfig	kernfs: add CONFIG_KERNFS	2014-02-07 16:08:57 -08:00
Makefile	sysfs, kernfs: move inode code to fs/kernfs/inode.c	2013-11-29 17:55:10 -08:00
dir.c	kernfs: implement kernfs_get_parent(), kernfs_name/path() and friends	2014-02-07 16:05:35 -08:00
file.c	sysfs: make sure read buffer is zeroed	2014-05-20 10:15:53 +09:00
group.c	sysfs: create bin_attributes under the requested group	2014-02-15 12:14:55 -08:00
mount.c	kernfs, sysfs, cgroup: restrict extra perm check on open to sysfs	2014-05-13 13:21:40 +02:00
symlink.c	kernfs: s/sysfs/kernfs/ in constants	2013-12-11 17:39:20 -08:00
sysfs.h	kernfs: s/sysfs_dirent/kernfs_node/ and rename its friends accordingly	2013-12-11 15:28:36 -08:00